The liver is a large organ that is found in the upper right side of the abdomen. It has two main functions. It helps remove toxins from the blood, and it makes bile and enzymes that help digest food.

There are two main types of cancer that may be found in the liver:

• Primary. This type of cancer starts in the cells that make up the liver. The most common form of primary liver cancer is hepatocellular carcinoma (HCC), also called malignant hepatoma. This can occur in people who have hepatitis B or C or cirrhosis of the liver. Other less common primary liver cancers include fibrolamellar carcinoma, cholangiocarcinoma and hepatoblastoma.
• Metastatic. This is cancer that has spread from other parts of the body. This is the most common type of liver cancer found in the United States.

What are the risk factors for liver cancer?
Doctors do not know the exact cause of liver cancer. However, certain factors have been shown to increase the risk of getting it. These risk factors include:

• Hepatitis B or hepatitis C. These are viruses that can be passed from person to person through blood or sexual contact. Babies may get the virus from their mothers. Hepatitis B is a very common infection in some parts of the world, including parts of Asia and Africa. Either hepatitis B or C can cause liver cancer after many years of chronic infection. There may be no symptoms, so the only way to know if you have hepatitis is to have a blood test.
• Cirrhosis of the liver. This occurs when the liver has been damaged and scar tissue forms. There are many causes for cirrhosis, including abuse of alcohol, use of some chemicals and drugs, infections with certain viruses or parasites or having certain autoimmune diseases. Only a small number of people with cirrhosis will get liver cancer.
• Aflatoxin. This is a toxin that is made by certain molds found on peanuts and other nuts or grains. Aflatoxin has been shown to cause liver cancer in some people. The U.S. Food and Drug Administration (FDA) tests the food supply in this country to be sure there are no high levels of aflatoxin.
• Age over 60. Being over 60 years old raises your risk for liver cancer.
• Tobacco use. Smoking increases your risk for liver cancer.
• Family history of liver cancer. Having someone in your family with liver cancer raises your risk of getting the disease.
• Male gender. Twice as many men as women get liver cancer.

What are the symptoms?
Early liver cancer is often silent - meaning there are no symptoms. As the cancer grows larger, symptoms may appear, including:

• Pain or discomfort in the upper right side of the abdomen. Sometimes the pain may go around to the back or up into the right shoulder.
• Loss of appetite or a feeling of fullness when you have only had a little to eat.
• Unintended weight loss. In advanced liver cancer, there may be dramatic weight loss.
• Bloated or swollen abdomen.
• Weakness or fatigue.
• Nausea or vomiting.
• Jaundice. Your skin and the whites of your eyes may become yellowish.
• Dark urine.

Many other conditions can cause these same symptoms, including hepatitis and other liver or gallbladder problems. Call your doctor right away if you have any of these symptoms.

Can liver cancer be prevented?
There is no known prevention for liver cancer, but some of the risk factors for it can be modified or prevented.

There is a vaccine to prevent hepatitis B, which is the leading cause of liver cancer worldwide. Hepatitis B vaccine is recommended for all children and for certain adults. Ask your doctor if you should be vaccinated. Doctors and researchers are also working on a vaccine to prevent hepatitis C.

You can also lower your risk for liver cancer if you quit smoking and address any problems of alcohol abuse.